Procedia Structural Integrity最新文献_第3页

Comparative Study of Fatigue Behavior and Microstructural Evolution in As-Built and Heat-Treated Additively Manufactured 316L Stainless Steel 增材制造316L不锈钢的疲劳行为和显微组织演变比较研究

Procedia Structural Integrity Pub Date : 2025-01-01 DOI: 10.1016/j.prostr.2025.06.083

Atef Hamada , Matias Jaskari , Walaa Abd-Elaziem , Tarek Allam , Antti Järvenpää

{"title":"Comparative Study of Fatigue Behavior and Microstructural Evolution in As-Built and Heat-Treated Additively Manufactured 316L Stainless Steel","authors":"Atef Hamada , Matias Jaskari , Walaa Abd-Elaziem , Tarek Allam , Antti Järvenpää","doi":"10.1016/j.prostr.2025.06.083","DOIUrl":"10.1016/j.prostr.2025.06.083","url":null,"abstract":"<div><div>This study investigates the influence of heat treatment (HT) at 900 °C on the fatigue resistance of 316L stainless steel fabricated through selective laser melting (SLM). Fully reversed, force-controlled fatigue tests were conducted on both as-built (AB) and HTed specimens to assess their cyclic deformation behavior and fatigue life. The fatigue fracture mechanisms were analyzed through detailed microstructural characterization using secondary electron imaging in a scanning electron microscope (SEM) and laser scanning confocal microscope LSCM. Results show that the HT 316L exhibited improved fatigue resistance and a longer fatigue life compared to the AB 316L. Fatigue cracking along dendritic columnar grains and the formation of slip bands were identified as key microstructural features in both AB and HT materials. In the AB material, the columnar dendritic grains and cellular substructure appear to create weak points at grain boundaries, facilitating fatigue crack initiation due to localized strain in persistent slip bands. However, HT at 900 °C effectively reduced the cellular substructure, promoting the formation of high-angle grain boundaries, which significantly enhanced the fatigue resistance of HT 316L.</div></div>","PeriodicalId":20518,"journal":{"name":"Procedia Structural Integrity","volume":"68 ","pages":"Pages 465-471"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A New Design for Mitigating Interfering Modes in Cruciform Specimens to Enhance Ultrasonic Fatigue Testing 减轻十字形试样干涉模态的新设计以提高超声疲劳测试

Procedia Structural Integrity Pub Date : 2025-01-01 DOI: 10.1016/j.prostr.2025.06.084

Diogo Montalvão , Sina Safari , Weston Chidzikwe , Phil Sewell , Pedro Costa , Luís Reis , Manuel Freitas

{"title":"A New Design for Mitigating Interfering Modes in Cruciform Specimens to Enhance Ultrasonic Fatigue Testing","authors":"Diogo Montalvão , Sina Safari , Weston Chidzikwe , Phil Sewell , Pedro Costa , Luís Reis , Manuel Freitas","doi":"10.1016/j.prostr.2025.06.084","DOIUrl":"10.1016/j.prostr.2025.06.084","url":null,"abstract":"<div><div>Cruciform specimens have been extensively used to simulate biaxial loading conditions in Ultrasonic Fatigue Testing (UFT), particularly within the Very High Cycle Fatigue (VHCF) regime. However, these specimens are often affected by interference from unintended flexural modes, such as the ‘flapping mode,’ which occur at frequencies near the desired axial mode, compromising the accuracy and reliability of the tests. To address this issue, a new specimen design has been developed to effectively separate the axial and flexural modes, thereby transforming the precision of fatigue testing. Finite Element Analysis (FEA) and experimental validation using Digital Image Correlation (DIC) were employed to optimise the geometry of the specimens, resulting in a substantial frequency separation between the interfering flexural modes and the axial mode. Through this redesign, mode coupling has been virtually eliminated, ensuring that the specimens deform as intended during testing. This breakthrough enables in-plane biaxial testing across the full range of biaxiality ratios, overcoming the previous challenges posed by mode coupling. Equibiaxial in-phase biaxial UFT with this type of cruciform specimen, previously considered largely theoretical in its practical application, has now been successfully realised through the innovations presented in this work.</div></div>","PeriodicalId":20518,"journal":{"name":"Procedia Structural Integrity","volume":"68 ","pages":"Pages 472-479"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimization of TMCP parameters to improve the mechanical properties of 201LN stainless steel for cryogenic applications 优化TMCP参数，提高低温应用201LN不锈钢的力学性能

Procedia Structural Integrity Pub Date : 2025-01-01 DOI: 10.1016/j.prostr.2025.06.091

Ahmed W. Abdelghany , Sumit Ghosh , Tun Tun Nyo , Ali Smith , Frank Hoffmann , Marta Muratori , Mahesh Somani

{"title":"Optimization of TMCP parameters to improve the mechanical properties of 201LN stainless steel for cryogenic applications","authors":"Ahmed W. Abdelghany , Sumit Ghosh , Tun Tun Nyo , Ali Smith , Frank Hoffmann , Marta Muratori , Mahesh Somani","doi":"10.1016/j.prostr.2025.06.091","DOIUrl":"10.1016/j.prostr.2025.06.091","url":null,"abstract":"<div><div>The study aims to optimise thermo-mechanically controlled processing (TMCP) parameters for 201LN stainless steel to achieve improved yield and tensile strengths, alongside excellent ductility, toughness, and fatigue properties. A 201LN alloy ingot (5.4 wt.% Ni and 7.0 wt.% Mn) was vacuum-cast and hot rolled into thick plates. Cylindrical samples were machined for uniaxial, two-step hot compression tests using a Gleeble simulator under six distinct TMCP schedules. The second step deformation was performed in the no-recrystallization regime at 850–1000 °C, followed by fast cooling to prevent precipitation and sensitization. Microstructural evolution was analysed using confocal laser scanning microscopy (CLSM) and Vickers hardness testing. Image analysis quantified grain size and distribution, revealing pancaked grain structures that contributed to dislocation or substructure strengthening. Hardness decreased with increasing second-step deformation temperature, with the highest values observed at 850 °C and 900 °C, showing increases of 55% and 45%, respectively, over the annealed condition. These findings demonstrate that TMCP enables tailored microstructures and properties in 201LN steel.</div></div>","PeriodicalId":20518,"journal":{"name":"Procedia Structural Integrity","volume":"68 ","pages":"Pages 520-526"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Anisotropy of gyroid and stochastic lattice structures under axial loading 轴向载荷作用下的陀螺和随机晶格结构的各向异性

Procedia Structural Integrity Pub Date : 2025-01-01 DOI: 10.1016/j.prostr.2025.06.106

Antti Järvenpää , Miguel Araya Calvo , Timo Rautio

{"title":"Anisotropy of gyroid and stochastic lattice structures under axial loading","authors":"Antti Järvenpää , Miguel Araya Calvo , Timo Rautio","doi":"10.1016/j.prostr.2025.06.106","DOIUrl":"10.1016/j.prostr.2025.06.106","url":null,"abstract":"<div><div>Lattice structures are an interesting possibility to tailor the strength-weight ratio and elasticity of metallic structures. In this study, Ti6Al4V gyroid and stochastic lattice structures with relative densities from 0.1 to 0.5 were manufactured by laser powder bed fusion technology, and the created structures were tested both under monotonic tension and compression to determine the strength properties and Young’s modulus.</div><div>The study showed clear differences in anisotropy between the gyroid and stochastic lattice structures. In general, the anisotropy in the yield strength (YS) was higher in stochastic lattices, but the ratio between compression and tensile YS remained at 1.25 for all the studied densities. Higher variation was seen with gyroid lattices showing a ratio from 1.00–1.23 depending on the density. Gyroid structures were also stronger in strength, and superior strength levels were observed in comparison to the values found in the literature. The anisotropy in Young’s modulus (E) was high and significant differences were observed with different densities, but the trend between the gyroid and stochastic structures was similar. Interestingly, the ratio between compression and tensile Young’s modulus decreased by increasing the density, being close to 0.5 at 0.44 g/cm3 and 0.15 at 2.2 g/cm3. The measured E values were low, making them an especially promising solution for medical bone replacements.</div></div>","PeriodicalId":20518,"journal":{"name":"Procedia Structural Integrity","volume":"68 ","pages":"Pages 619-625"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The study of critical defects in selective laser melting material under very high cycle fatigue loading 高周疲劳载荷下选择性激光熔化材料临界缺陷的研究

Procedia Structural Integrity Pub Date : 2025-01-01 DOI: 10.1016/j.prostr.2025.06.018

Ilia Nikitin , Alexander Nikitin , Andrey Shanyavskiy , Boris Stratula

{"title":"The study of critical defects in selective laser melting material under very high cycle fatigue loading","authors":"Ilia Nikitin , Alexander Nikitin , Andrey Shanyavskiy , Boris Stratula","doi":"10.1016/j.prostr.2025.06.018","DOIUrl":"10.1016/j.prostr.2025.06.018","url":null,"abstract":"<div><div>This paper focuses on the fatigue behaviour of materials produced by selective laser melting. It highlights that internal defects or structural imperfections serve as potential fatigue crack initiation sites. The role of internal imperfections of microstructure becomes more pronounced in the very high cycle fatigue regime. The study is focused on the numerical simulations of the selected laser melting process to discover the nature, shape and distribution of typical defects based on laser beam parameters and scanning strategies. The non-linear heat conductivity problem with a moving phase boundary is solved for both single and multiple laser tracks. The problem is formulated in enthalpy terms. Two primary types of defects are discovered: not-melted zones and re-melted zones. These types of defects are simulated in the computer aided model of a very high cycle fatigue specimen. The not-melted zones are associated with localized regions of reduced elastic modulus, whereas the re-melted zones are associated with regions of slightly elevated values of elastic modulus. Fatigue life predictions, performed using multi regime fatigue fracture model, show a significant difference in fatigue life between specimens containing not-melted and re-melted defects. Under identical loading condition, the fatigue life of specimen with not-melted defects is about 10 times shorter compared to homogeneous material.</div></div>","PeriodicalId":20518,"journal":{"name":"Procedia Structural Integrity","volume":"68 ","pages":"Pages 24-31"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The effect of thread length in cancellous bone fixation under shear loading: A biomechanical study 剪切载荷下螺纹长度对松质骨固定的影响：一项生物力学研究

Procedia Structural Integrity Pub Date : 2025-01-01 DOI: 10.1016/j.prostr.2025.06.030

P. Langourani-Kosteletou , G. Chelidonis , E.D. Pasiou , O. Savvidou , S.K. Kourkoulis

{"title":"The effect of thread length in cancellous bone fixation under shear loading: A biomechanical study","authors":"P. Langourani-Kosteletou , G. Chelidonis , E.D. Pasiou , O. Savvidou , S.K. Kourkoulis","doi":"10.1016/j.prostr.2025.06.030","DOIUrl":"10.1016/j.prostr.2025.06.030","url":null,"abstract":"<div><div>The thread length of bone screws is a crucial design parameter directly related to the length of the thread engagement in the bone. For porous materials, like cancellous bone, the length of engagement is correlated with the holding power of screws. The objective of this study is to assess the effect of the thread length in fixation under shear loading, a relatively unexplored area of investigation. For this purpose, sawbone blocks were used as a substitute for cancellous bone, fixed with either a single 6.5 solid-core cancellous screw with a thread length of 16 mm or a single screw with a 32 mm thread length (lag by design). The experiments (shear loading of the constructs) were carried out using an MTS Insight frame. The stiffness, proportionality limit, conventional yield load, and yield displacement were determined for each test piece. The results indicated that the constructs fixed with longer threaded screws had statistically significantly greater stiffness, proportionality limit, and yield force compared to the constructs fixed with shorter threaded screws. This study suggests that the length of thread engagement may affect the resistance of fixation to shear loading.</div></div>","PeriodicalId":20518,"journal":{"name":"Procedia Structural Integrity","volume":"68 ","pages":"Pages 112-118"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Effect of Alternating Wet-Dry Conditions in the Fatigue Life of S355G10+M Steel under Corrosion-Fatigue Testing 干湿交替条件对S355G10+M钢腐蚀疲劳试验疲劳寿命的影响

Procedia Structural Integrity Pub Date : 2025-01-01 DOI: 10.1016/j.prostr.2025.06.053

M. Álvarez , A. Vergara , M. Escalero , M. Olave

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Enhancing Crack Resistance and Strength of Recycled Aggregate Concrete with End-of-Life Tire Steel Fibers 废旧轮胎钢纤维增强再生骨料混凝土抗裂性和强度

Procedia Structural Integrity Pub Date : 2025-01-01 DOI: 10.1016/j.prostr.2025.06.047

Asad Zia , Jaroslav Prokop , Ivan Holly

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Laser shape setting feasibility for promoting shape memory effect in thin Ti rich-NiTi wires 提高富钛镍钛细线形状记忆效应的激光成形可行性

Procedia Structural Integrity Pub Date : 2025-01-01 DOI: 10.1016/j.prostr.2025.07.017

Carlo Alberto Biffi , Gloria Ischia , Stefano Gialanella , Ausonio Tuissi

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Effect of solid-solution temperature on the microstructure and mechanical properties in low-cobalt secondary hardening ultra-high strength steel 固溶温度对低钴二次硬化超高强度钢组织和力学性能的影响

Procedia Structural Integrity Pub Date : 2025-01-01 DOI: 10.1016/j.prostr.2025.07.016

Haofei Zhu , Zhiping Xiong , Jianwen Mao , Xingwang Cheng

{"title":"Effect of solid-solution temperature on the microstructure and mechanical properties in low-cobalt secondary hardening ultra-high strength steel","authors":"Haofei Zhu , Zhiping Xiong , Jianwen Mao , Xingwang Cheng","doi":"10.1016/j.prostr.2025.07.016","DOIUrl":"10.1016/j.prostr.2025.07.016","url":null,"abstract":"<div><div>The effects of solid-solution temperature on the microstructure and mechanical properties of low-cobalt M<sub>2</sub>C and NiAl co-precipitated secondary hardening steel were investigated. With increasing solid-solution temperature, the microstructure undergoes complex evolution, characterized by an increase in retained austenite, dissolution of primary M<sub>7</sub>C<sub>3</sub> carbides, and growth of prior austenite grains. Correspondingly, the yield strength and impact toughness in both quenched and aged conditions initially improve. This is attributed to the dissolution of the primary M<sub>7</sub>C<sub>3</sub> carbides, which enhances the precipitation strengthening of M<sub>2</sub>C carbides and inhibits crack nucleation, thereby improving both strength and toughness. However, when the solid-solution temperature exceeds 900 °C, the coarsening of prior austenite grains leads to a reduction in Hall-Petch strengthening and decreased crack propagation resistance, resulting in a decline in yield strength and toughness in the aged state. The optimal solid-solution temperature is found to be 900 °C, where an excellent balance between strength and toughness is achieved.</div></div>","PeriodicalId":20518,"journal":{"name":"Procedia Structural Integrity","volume":"69 ","pages":"Pages 113-120"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144587883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0